Method for manufacturing annular member

A method for manufacturing an annular member, the method comprising:

• providing a first restraining mold and a second restraining mold, each of which is formed in an annular shape, in an axial direction of a cylindrical member such that inner circumferential surfaces of the first restraining mold and the second restraining mold abut against an outer circumferential surface of the cylindrical member;
• providing a third restraining mold and a fourth restraining mold, each of which is formed in an annular shape, such that outer circumferential surfaces of the third restraining mold and the fourth restraining mold abut against an inner circumferential surface of the cylindrical member at positions which respectively correspond to positions of the first restraining mold and the second restraining mold in the axial direction;
• moving a roll that includes a first disc-shaped urging portion that abuts against an outer surface of the first restraining mold and a second disc-shaped urging portion that abuts against an outer surface of the second restraining mold, the first and second disc-shaped urging portions being separated by a cushioning portion having a gap from an outer surface of a fifth restraining mold, a mandrel abutting an inner circumferential surface of a sixth restraining mold;
• applying a shear force that shifts a portion of the cylindrical member abutting the second restraining mold and the fourth restraining mold by urging the first restraining mold with the first disc-shaped urging portion;
• and rotating each of the cylindrical member and the roll so as to cut and separate the cylindrical member.